Prime Minister Boris Johnson has offered an "unreserved apology" after a new report found that 350,000 predominantly black and Asian service personnel have not been formally remembered in the same way as their white comrades.
Following the report's publication, the prime minister said: "During the First World War, millions of people from Africa, Asia, the Caribbean and the Middle East fought for Britain in the struggle against tyranny.
"Their contribution to victory was immense, not just in numerical terms but in their courage and valour, and many paid the ultimate price so that we might live in peace and freedom today.
"I am deeply troubled by the findings of the special committee that not all of our war dead were commemorated with equal care and reverence.
"On behalf of the government, I offer an unreserved apology."
The inquiry commissioned by the Commonwealth War Graves Commission (CWGC),found that between 45,000 and 54,000 individuals of predominantly Asian, Middle Eastern and African origin who died during World War I were commemorated “unequally”.
Most of them were commemorated by memorials that did not carry their names.
The CWGC works to commemorate those from Commonwealth forces who were killed in the two world wars and to ensure all those killed are remembered in the same way, with their name engraved either on a headstone over an identified grave or on a memorial to the missing.
Mr Johnson said that he welcomed the fact that the Commonwealth War Graves Commission has accepted all of the committee's recommendations and that it will now re-examine records and make amends wherever possible.
"Our shared duty is to honour and remember all those, wherever they lived and whatever their background, who laid down their lives for our freedoms at the moment of greatest peril," he said.
According to Thursday’s report, another officer, who later worked for the CWGC’s predecessor – the Imperial War Graves Commission, had said: “Most of the natives who died are of a semi-savage nature”, and concluded that erecting headstones would be a waste of public money.
The inquiry said decisions that led to the failure to commemorate the dead properly – or even at all – was the result of a lack of information, errors inherited from other organisations, and the opinions of colonial administrators.
"Underpinning all these decisions, however, were the entrenched prejudices, preconceptions and pervasive racism of contemporary imperial attitudes," the report said.
In its response to the report, the CWGC said it "acknowledges that the commission failed to fully carry out its responsibilities at the time and accepts the findings and failings identified in this report and we apologise unreservedly for them".
CWGC director general Claire Horton said: "The events of a century ago were wrong then and are wrong now.
"We recognise the wrongs of the past and are deeply sorry and will be acting immediately to correct them."
David Lammy, the shadow justice secretary, said: "No apology can ever make up for the indignity suffered by the unremembered.
"However, this apology does offer the opportunity for us as a nation to work through this ugly part of our history - and properly pay our respects to every soldier who has sacrificed their life for us."